Red Cone and Hollywood Chute: Kick Test Results, Snow Available for Transport

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SNOWPACK OBSERVATION
Submission Info
Forecaster
Wednesday, February 21, 2018 - 2:00pm
Red Flags: 
Whumphing noises, shooting cracks, or collapsing
Recent loading by new snow, wind, or rain
37° 35' 44.52" N, 119° 1' 38.28" W
Snowpit Observations
More detailed information about the snowpack: 

Toured up the standard approach to the top of Red Cone this afternoon to see if the Top of the Bowl and Hollywood Chute had developed small wind slabs and to take boot penetration in the large fetches S and SE of the Crest.

Several small (D 0.5) kick test results in recently deposited wind slabs at the top of Hollywood Chute (see photos, photos enhanced because of flat light). The top of the Chute had the largest results (still very small). Slope was 38 degrees at 10,400', aspect was N, slabs were about 15cm deep and about 8'x5' running about 20-30'. Slab was 4F wind deposited rounds, weak layer was F- wind blown fragments, and the bed surface was P hard previously deposited wind board. Other kick tests on N and even W facing around the top of Red Cone Bowl had some cracking and little chunks that broke off, but nothing I'd even rate on the D scale.

Walked around in the fetches just upwind of Red Cone and the Hollywood area (upwind given a W-SW-S wind) and took ski and boot penetration in 8 different places. Average boot pen was 18cm, but some areas that are frequently scoured were almost bare already while others are still stocked with very soft and cold snow available for transport. Given continuous moderate winds, fresh wind slabs could become as large as 54 to 90cm deep in specific areas with the better stocked upwind slopes, before any new snow falls.

Snow surfaces, besides the isolated wind deposits, were generally 10-15cm of soft F hard unconsolidated snow. E and S aspects were starting to show some settlement in the top few centemeters but were still F+ hard (soft). Areas that have near surface facets under the recent storm snow may still be faceting. Temperature gradient between surface and -10cm was about 2 deg. C on a NW facing slope, but hand shears with the same near surface structure failed roughly with moderate to hard force so it's hard to stay that that layer is weakening to threshold just yet. Just worth noting that this is the second place on the Mammoth Crest I've seen storm snow or wind broken fragmented snow sitting directly on top of facets (other place was a N facing slope with a similar elevation, 10,200', near Hammil Bowl).

Very light showers (S-1) started as I turned down around 2pm with light SW wind. No snow was blowing around as of then. Sky was broken to overcast. Temperature was warmer than I expected with the clouds likely holding in some of the sensible heat. Still cold though.

Snowpack photos: 
Kick Test Results
Kick Test Results
Weather Observations
Blowing Snow: 
Air temperature: 
Wind Speed: 
Precipitation: 
Air temperature trend: 
Wind Direction: 
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